DUAL ELEMENT PYROELECTRIC MOTION AND PRESENCE DETECTOR

• US 20160138976A1
• Filed: 01/22/2016
• Published: 05/19/2016
• Est. Priority Date: 04/22/2013
• Status: Active Grant

• Current Assignee: Excelitas Technologies Singapore Pte., Ltd.
• Original Assignee: Excelitas Technologies Singapore Pte., Ltd.
• Inventors: Schilz, Juergen, Barlow, Arthur John, Schmidt, Wolfgang
• Granted Patent: US 10,018,510 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01J 5/0025 Living bodies ear thermometers G01J5/0011; detecting, measuring or recording for diagnostic purposes A61B5/00
• CPC Class Codes: G01J 5/12 using thermoelectric elements, e.g. thermocouples
• CPC Class Codes: G08B 13/193 using focusing means

Abstract

An apparatus configured to sense presence and motion in a monitored space is presented. The apparatus includes a dual-element assembly with a first thermal sensing element and a second thermal sensing element configured to produce a direct current output that is sustained at a level substantially proportional to an amount of thermal energy being received at the thermal sensing elements. A lens array (or equivalent optics) is coupled to the elements, having a plurality of lenses directing incident thermal energy from a plurality of optically-defined spatial zones onto the sensing elements. An electronic circuitry is configured to read a resulting signal of the dual-element assembly and an individual output signal of each the first thermal sensing element and the second thermal sensing element.

Claims

1. An apparatus configured to sense presence and motion in a monitored space, the apparatus comprising:

a dual-element assembly further comprising a first thermal sensing element and a second thermal sensing element further comprising a first terminal having a first polarity and a second terminal having a second polarity;

a lens array coupled to the one or more thermal sensing elements, wherein the lens array comprises a plurality of lenses, each of which is configured to direct incident thermal energy from a respective one of a plurality of optically-defined spatial zones located within the monitored space onto the first and/or the second thermal sensing element; and

an electronic circuitry in electrical communication with dual-element assembly and configured to read a resulting signal of the dual-element assembly and an individual output signal of each the first thermal sensing element and the second thermal sensing element,

wherein the electronic circuitry, the first thermal sensing element and the second thermal sensing element are electrically connected at a connection point comprising their first terminals or their second terminals.

2. The apparatus of claim 1, wherein the electronic circuitry further comprises a digital interface.

3. The apparatus of claim 1, wherein the electronic circuitry further comprises an interrupt terminal.

4. The apparatus of claim 3, wherein the electronic circuitry is configured to react to a signal on the interrupt terminal denoting motion, presence and/or a temperature level and/or pattern.

5. The apparatus of claim 1, wherein the electronic circuitry further comprises an analog to digital converter.

6. The apparatus of claim 1, wherein the first thermal sensing element and the second thermal sensing element each further comprise one of the group consisting of a microelectromechanical system (MEMS) infrared sensor, a thermopile, a bolometer, and/or an infrared intrinsic or extrinsic semiconductor.

7. The apparatus of claim 1, wherein the lens array produces alternating regions of relatively high output signal to the incident thermal energy and regions of relatively low output signal to the incident thermal energy.

8. The apparatus of claim 7, wherein the regions of relatively low output signal are at edges of the lenses or between the lenses in the lens array.

9. The apparatus of claim 7, wherein the regions of relatively low output signal correspond to virtual dividing lines between the spatial zones within the monitored space.

10. The apparatus of claim 1, wherein the lenses of the lens array are selected from the group consisting of Fresnel lens arrays, Fresnel zone arrays, holographic optical elements, diffractive optical elements, refractive optical elements, binary optical elements, and grid patterns.

11. The apparatus of claim 1, wherein the lenses are optical patterns not physically locatable over the lens array.

12. The apparatus of claim 1 further comprising a computer-based processor coupled to the electronic circuitry and a computer-based memory storage device coupled to the processor,

wherein the memory storage device stores instructions that, when executed by the processor, cause the processor to determine, based on data received from the one or more thermal sensing devices, whether there is a living being present in or moving about the monitored space.

13. The apparatus of claim 8, wherein the one or more thermal sensing elements, the lens array, the processor and the memory storage device are contained in a single chip level package.

14. The apparatus of claim 1, wherein a first lens of the lens array is configured to the direct incident thermal energy from a corresponding one of the physical zones in the monitored space onto a first one of the thermal sensing elements and onto a second one of the thermal sensing devices.

15. The apparatus of claim 1, wherein a first lens of the lens array is configured to direct the incident thermal energy from a corresponding first one of the physical zones in the monitored spaces onto the thermal sensing element, but not the second thermal sensing element, and wherein a second lens of the lens array is configured to direct the incident thermal energy from a corresponding second one of the physical zones in the monitored space onto the second thermal sensing element, but not the first thermal sensing element.

16. The apparatus of claim 1, wherein the one or more thermal sensing elements are sensitive to radiation having a wavelength between 4 μ

m and 20 μ

m.

17. The apparatus of claim 1 adapted to determine a temperature value over a total of the monitored space by evaluating an overall incoming thermal signal strength.

18. The apparatus of claim 1, wherein the first and second thermal sensing elements are each configured to produce a direct current output that is sustained at a level substantially proportional to an amount of thermal energy being received at the thermal sensing elements.